Every day is more fashionable the so-called High Intensity Interval Training (HIIT), a training modality that stands out for making the practice of exercise as short as possible and without loss of effectiveness. However, these kinds of somewhat “aggressive” approaches always generate certain doubts and fears about their suitability in people with certain pathologies. Especially those of cardiometabolic origin, as they are often considered quite delicate situations and where safety is a relevant factor.
The truth is that studies on the subject were already addressed several decades ago. One of the first was published in 1981, “Effects of 12 months of intense exercise training on ischemic ST-segment depression in patients with coronary artery disease”, focused on using intense training in people with coronary heart disease. The authors found that after a 12-month program the electrocardiogram showed improvements in the risk profile. However, some of the studies conducted later obtained less favorable and quite heterogeneous results, so the approach of using intense exercise as therapy among such patients lost interest for a few years.
The popularization of HIIT has again aroused the curiosity of experts and scientists, so lately research has reappeared in specialized scientific journals. There are not too many, but if a significant amount that begins to be worthy of consideration. And in order to unify and summarize the most relevant studies and their results, a few months ago the metataanalysis “High-intensity interval training in patients with lifestyle-induced cardiometabolic disease- a systematic review and meta-analysis” (2014) was published. This review brought together the last 10 HIIT studies conducted with patients who had suffered from coronary heart disease, heart attack, hypertension, metabolic syndrome or obesity, all conducted over the past decade.
Here is a summary of your main conclusions:
Form state (measured by respiratory or aerobic capacity, VO2max): In all but one studies HIIT achieved better results than “normal” exercise (continuous and moderate intensity – MICT).
Metabolic and cardiovascular health indicators: In this case the results are much more heterogeneous. Either way, at least the same improvements are achieved as with normal exercise and, in quite a few cases, greater.
Safety: This aspect is important, as we are talking about high-risk patients. However, in this case the evidence is not very solid, as the researchers are not explicit explaining their protocols for measuring adverse effects and only four of the ten studies explicitly say that they have not been detected. In the rest they are simply not mentioned. Either way, in all cases the implementation of hiIT is done progressively and very controlled and in no case negative effects are reported.
In short, it could be said that in the light of current evidence, HIIT seems useful for achieving promising results in this type of patient. While it also seems quite clear that further research is needed, for example by analysing their effect for each of the indicators, but above all on security-related aspects, especially for the design of the most reliable and secure intervention protocols. While all these issues are cleared up, if you don’t have health problems you can start practicing it, following any of the multiple sessions you can find on Youtube, such as this